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@@ -0,0 +1,726 @@
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+/*
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+ * Point-to-Point Tunneling Protocol for Linux
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+ *
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+ * Authors: Dmitry Kozlov <xeb@mail.ru>
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+ *
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+ * This program is free software; you can redistribute it and/or
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+ * modify it under the terms of the GNU General Public License
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+ * as published by the Free Software Foundation; either version
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+ * 2 of the License, or (at your option) any later version.
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+ *
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+ */
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+
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+#include <linux/string.h>
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+#include <linux/module.h>
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+#include <linux/kernel.h>
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+#include <linux/slab.h>
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+#include <linux/errno.h>
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+#include <linux/netdevice.h>
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+#include <linux/net.h>
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+#include <linux/skbuff.h>
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+#include <linux/vmalloc.h>
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+#include <linux/init.h>
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+#include <linux/ppp_channel.h>
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+#include <linux/ppp_defs.h>
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+#include <linux/if_pppox.h>
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+#include <linux/if_ppp.h>
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+#include <linux/notifier.h>
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+#include <linux/file.h>
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+#include <linux/in.h>
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+#include <linux/ip.h>
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+#include <linux/netfilter.h>
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+#include <linux/netfilter_ipv4.h>
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+#include <linux/version.h>
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+#include <linux/rcupdate.h>
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+#include <linux/spinlock.h>
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+
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+#include <net/sock.h>
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+#include <net/protocol.h>
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+#include <net/ip.h>
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+#include <net/icmp.h>
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+#include <net/route.h>
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+#include <net/gre.h>
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+
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+#include <linux/uaccess.h>
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+
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+#define PPTP_DRIVER_VERSION "0.8.5"
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+
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+#define MAX_CALLID 65535
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+
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+static DECLARE_BITMAP(callid_bitmap, MAX_CALLID + 1);
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+static struct pppox_sock **callid_sock;
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+
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+static DEFINE_SPINLOCK(chan_lock);
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+
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+static struct proto pptp_sk_proto __read_mostly;
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+static struct ppp_channel_ops pptp_chan_ops;
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+static const struct proto_ops pptp_ops;
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+
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+#define PPP_LCP_ECHOREQ 0x09
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+#define PPP_LCP_ECHOREP 0x0A
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+#define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
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+
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+#define MISSING_WINDOW 20
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+#define WRAPPED(curseq, lastseq)\
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+ ((((curseq) & 0xffffff00) == 0) &&\
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+ (((lastseq) & 0xffffff00) == 0xffffff00))
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+
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+#define PPTP_GRE_PROTO 0x880B
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+#define PPTP_GRE_VER 0x1
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+
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+#define PPTP_GRE_FLAG_C 0x80
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+#define PPTP_GRE_FLAG_R 0x40
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+#define PPTP_GRE_FLAG_K 0x20
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+#define PPTP_GRE_FLAG_S 0x10
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+#define PPTP_GRE_FLAG_A 0x80
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+
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+#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C)
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+#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R)
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+#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K)
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+#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S)
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+#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A)
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+
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+#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
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+struct pptp_gre_header {
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+ u8 flags;
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+ u8 ver;
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+ u16 protocol;
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+ u16 payload_len;
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+ u16 call_id;
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+ u32 seq;
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+ u32 ack;
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+} __packed;
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+
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+static struct pppox_sock *lookup_chan(u16 call_id, __be32 s_addr)
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+{
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+ struct pppox_sock *sock;
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+ struct pptp_opt *opt;
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+
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+ rcu_read_lock();
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+ sock = rcu_dereference(callid_sock[call_id]);
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+ if (sock) {
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+ opt = &sock->proto.pptp;
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+ if (opt->dst_addr.sin_addr.s_addr != s_addr)
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+ sock = NULL;
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+ else
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+ sock_hold(sk_pppox(sock));
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+ }
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+ rcu_read_unlock();
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+
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+ return sock;
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+}
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+
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+static int lookup_chan_dst(u16 call_id, __be32 d_addr)
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+{
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+ struct pppox_sock *sock;
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+ struct pptp_opt *opt;
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+ int i;
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+
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+ rcu_read_lock();
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+ for (i = find_next_bit(callid_bitmap, MAX_CALLID, 1); i < MAX_CALLID;
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+ i = find_next_bit(callid_bitmap, MAX_CALLID, i + 1)) {
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+ sock = rcu_dereference(callid_sock[i]);
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+ if (!sock)
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+ continue;
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+ opt = &sock->proto.pptp;
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+ if (opt->dst_addr.call_id == call_id &&
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+ opt->dst_addr.sin_addr.s_addr == d_addr)
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+ break;
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+ }
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+ rcu_read_unlock();
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+
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+ return i < MAX_CALLID;
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+}
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+
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+static int add_chan(struct pppox_sock *sock)
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+{
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+ static int call_id;
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+
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+ spin_lock(&chan_lock);
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+ if (!sock->proto.pptp.src_addr.call_id) {
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+ call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, call_id + 1);
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+ if (call_id == MAX_CALLID) {
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+ call_id = find_next_zero_bit(callid_bitmap, MAX_CALLID, 1);
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+ if (call_id == MAX_CALLID)
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+ goto out_err;
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+ }
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+ sock->proto.pptp.src_addr.call_id = call_id;
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+ } else if (test_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap))
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+ goto out_err;
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+
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+ set_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
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+ rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id], sock);
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+ spin_unlock(&chan_lock);
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+
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+ return 0;
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+
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+out_err:
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+ spin_unlock(&chan_lock);
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+ return -1;
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+}
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+
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+static void del_chan(struct pppox_sock *sock)
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+{
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+ spin_lock(&chan_lock);
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+ clear_bit(sock->proto.pptp.src_addr.call_id, callid_bitmap);
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+ rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id], NULL);
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+ spin_unlock(&chan_lock);
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+ synchronize_rcu();
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+}
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+
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+static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
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+{
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+ struct sock *sk = (struct sock *) chan->private;
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+ struct pppox_sock *po = pppox_sk(sk);
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+ struct pptp_opt *opt = &po->proto.pptp;
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+ struct pptp_gre_header *hdr;
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+ unsigned int header_len = sizeof(*hdr);
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+ int err = 0;
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+ int islcp;
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+ int len;
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+ unsigned char *data;
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+ __u32 seq_recv;
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+
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+
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+ struct rtable *rt;
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+ struct net_device *tdev;
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+ struct iphdr *iph;
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+ int max_headroom;
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+
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+ if (sk_pppox(po)->sk_state & PPPOX_DEAD)
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+ goto tx_error;
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+
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+ {
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+ struct flowi fl = { .oif = 0,
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+ .nl_u = {
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+ .ip4_u = {
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+ .daddr = opt->dst_addr.sin_addr.s_addr,
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+ .saddr = opt->src_addr.sin_addr.s_addr,
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+ .tos = RT_TOS(0) } },
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+ .proto = IPPROTO_GRE };
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+ err = ip_route_output_key(&init_net, &rt, &fl);
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+ if (err)
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+ goto tx_error;
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+ }
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+ tdev = rt->dst.dev;
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+
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+ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph) + sizeof(*hdr) + 2;
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+
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+ if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
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+ struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
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+ if (!new_skb) {
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+ ip_rt_put(rt);
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+ goto tx_error;
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+ }
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+ if (skb->sk)
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+ skb_set_owner_w(new_skb, skb->sk);
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+ kfree_skb(skb);
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+ skb = new_skb;
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+ }
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+
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+ data = skb->data;
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+ islcp = ((data[0] << 8) + data[1]) == PPP_LCP && 1 <= data[2] && data[2] <= 7;
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+
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+ /* compress protocol field */
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+ if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp)
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+ skb_pull(skb, 1);
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+
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+ /* Put in the address/control bytes if necessary */
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+ if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) {
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+ data = skb_push(skb, 2);
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+ data[0] = PPP_ALLSTATIONS;
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+ data[1] = PPP_UI;
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+ }
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+
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+ len = skb->len;
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+
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+ seq_recv = opt->seq_recv;
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+
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+ if (opt->ack_sent == seq_recv)
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+ header_len -= sizeof(hdr->ack);
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+
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+ /* Push down and install GRE header */
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+ skb_push(skb, header_len);
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+ hdr = (struct pptp_gre_header *)(skb->data);
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+
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+ hdr->flags = PPTP_GRE_FLAG_K;
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+ hdr->ver = PPTP_GRE_VER;
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+ hdr->protocol = htons(PPTP_GRE_PROTO);
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+ hdr->call_id = htons(opt->dst_addr.call_id);
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+
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+ hdr->flags |= PPTP_GRE_FLAG_S;
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+ hdr->seq = htonl(++opt->seq_sent);
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+ if (opt->ack_sent != seq_recv) {
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+ /* send ack with this message */
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+ hdr->ver |= PPTP_GRE_FLAG_A;
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+ hdr->ack = htonl(seq_recv);
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+ opt->ack_sent = seq_recv;
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+ }
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+ hdr->payload_len = htons(len);
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+
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+ /* Push down and install the IP header. */
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+
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+ skb_reset_transport_header(skb);
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+ skb_push(skb, sizeof(*iph));
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+ skb_reset_network_header(skb);
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+ memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
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+ IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED);
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+
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+ iph = ip_hdr(skb);
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+ iph->version = 4;
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+ iph->ihl = sizeof(struct iphdr) >> 2;
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+ if (ip_dont_fragment(sk, &rt->dst))
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+ iph->frag_off = htons(IP_DF);
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+ else
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+ iph->frag_off = 0;
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+ iph->protocol = IPPROTO_GRE;
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+ iph->tos = 0;
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+ iph->daddr = rt->rt_dst;
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+ iph->saddr = rt->rt_src;
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+ iph->ttl = dst_metric(&rt->dst, RTAX_HOPLIMIT);
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+ iph->tot_len = htons(skb->len);
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+
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+ skb_dst_drop(skb);
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+ skb_dst_set(skb, &rt->dst);
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+
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+ nf_reset(skb);
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+
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+ skb->ip_summed = CHECKSUM_NONE;
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+ ip_select_ident(iph, &rt->dst, NULL);
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+ ip_send_check(iph);
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+
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+ ip_local_out(skb);
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+
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+tx_error:
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+ return 1;
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+}
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+
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+static int pptp_rcv_core(struct sock *sk, struct sk_buff *skb)
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+{
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+ struct pppox_sock *po = pppox_sk(sk);
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+ struct pptp_opt *opt = &po->proto.pptp;
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+ int headersize, payload_len, seq;
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+ __u8 *payload;
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+ struct pptp_gre_header *header;
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+
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+ if (!(sk->sk_state & PPPOX_CONNECTED)) {
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+ if (sock_queue_rcv_skb(sk, skb))
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+ goto drop;
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+ return NET_RX_SUCCESS;
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+ }
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+
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+ header = (struct pptp_gre_header *)(skb->data);
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+
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+ /* test if acknowledgement present */
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+ if (PPTP_GRE_IS_A(header->ver)) {
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+ __u32 ack = (PPTP_GRE_IS_S(header->flags)) ?
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+ header->ack : header->seq; /* ack in different place if S = 0 */
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+
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+ ack = ntohl(ack);
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+
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+ if (ack > opt->ack_recv)
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+ opt->ack_recv = ack;
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+ /* also handle sequence number wrap-around */
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+ if (WRAPPED(ack, opt->ack_recv))
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+ opt->ack_recv = ack;
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+ }
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+
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+ /* test if payload present */
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+ if (!PPTP_GRE_IS_S(header->flags))
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+ goto drop;
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+
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+ headersize = sizeof(*header);
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+ payload_len = ntohs(header->payload_len);
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+ seq = ntohl(header->seq);
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+
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+ /* no ack present? */
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+ if (!PPTP_GRE_IS_A(header->ver))
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+ headersize -= sizeof(header->ack);
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+ /* check for incomplete packet (length smaller than expected) */
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+ if (skb->len - headersize < payload_len)
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+ goto drop;
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+
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+ payload = skb->data + headersize;
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+ /* check for expected sequence number */
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+ if (seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq)) {
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+ if ((payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) &&
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+ (PPP_PROTOCOL(payload) == PPP_LCP) &&
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+ ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)))
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+ goto allow_packet;
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+ } else {
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+ opt->seq_recv = seq;
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+allow_packet:
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+ skb_pull(skb, headersize);
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+
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+ if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) {
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+ /* chop off address/control */
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+ if (skb->len < 3)
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+ goto drop;
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+ skb_pull(skb, 2);
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+ }
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+
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+ if ((*skb->data) & 1) {
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+ /* protocol is compressed */
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+ skb_push(skb, 1)[0] = 0;
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+ }
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+
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+ skb->ip_summed = CHECKSUM_NONE;
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+ skb_set_network_header(skb, skb->head-skb->data);
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+ ppp_input(&po->chan, skb);
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+
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+ return NET_RX_SUCCESS;
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+ }
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+drop:
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+ kfree_skb(skb);
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+ return NET_RX_DROP;
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+}
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+
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+static int pptp_rcv(struct sk_buff *skb)
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+{
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+ struct pppox_sock *po;
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+ struct pptp_gre_header *header;
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+ struct iphdr *iph;
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+
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+ if (skb->pkt_type != PACKET_HOST)
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+ goto drop;
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+
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|
|
+ if (!pskb_may_pull(skb, 12))
|
|
|
+ goto drop;
|
|
|
+
|
|
|
+ iph = ip_hdr(skb);
|
|
|
+
|
|
|
+ header = (struct pptp_gre_header *)skb->data;
|
|
|
+
|
|
|
+ if (ntohs(header->protocol) != PPTP_GRE_PROTO || /* PPTP-GRE protocol for PPTP */
|
|
|
+ PPTP_GRE_IS_C(header->flags) || /* flag C should be clear */
|
|
|
+ PPTP_GRE_IS_R(header->flags) || /* flag R should be clear */
|
|
|
+ !PPTP_GRE_IS_K(header->flags) || /* flag K should be set */
|
|
|
+ (header->flags&0xF) != 0) /* routing and recursion ctrl = 0 */
|
|
|
+ /* if invalid, discard this packet */
|
|
|
+ goto drop;
|
|
|
+
|
|
|
+ po = lookup_chan(htons(header->call_id), iph->saddr);
|
|
|
+ if (po) {
|
|
|
+ skb_dst_drop(skb);
|
|
|
+ nf_reset(skb);
|
|
|
+ return sk_receive_skb(sk_pppox(po), skb, 0);
|
|
|
+ }
|
|
|
+drop:
|
|
|
+ kfree_skb(skb);
|
|
|
+ return NET_RX_DROP;
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_bind(struct socket *sock, struct sockaddr *uservaddr,
|
|
|
+ int sockaddr_len)
|
|
|
+{
|
|
|
+ struct sock *sk = sock->sk;
|
|
|
+ struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
|
|
|
+ struct pppox_sock *po = pppox_sk(sk);
|
|
|
+ struct pptp_opt *opt = &po->proto.pptp;
|
|
|
+ int error = 0;
|
|
|
+
|
|
|
+ lock_sock(sk);
|
|
|
+
|
|
|
+ opt->src_addr = sp->sa_addr.pptp;
|
|
|
+ if (add_chan(po)) {
|
|
|
+ release_sock(sk);
|
|
|
+ error = -EBUSY;
|
|
|
+ }
|
|
|
+
|
|
|
+ release_sock(sk);
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr,
|
|
|
+ int sockaddr_len, int flags)
|
|
|
+{
|
|
|
+ struct sock *sk = sock->sk;
|
|
|
+ struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr;
|
|
|
+ struct pppox_sock *po = pppox_sk(sk);
|
|
|
+ struct pptp_opt *opt = &po->proto.pptp;
|
|
|
+ struct rtable *rt;
|
|
|
+ int error = 0;
|
|
|
+
|
|
|
+ if (sp->sa_protocol != PX_PROTO_PPTP)
|
|
|
+ return -EINVAL;
|
|
|
+
|
|
|
+ if (lookup_chan_dst(sp->sa_addr.pptp.call_id, sp->sa_addr.pptp.sin_addr.s_addr))
|
|
|
+ return -EALREADY;
|
|
|
+
|
|
|
+ lock_sock(sk);
|
|
|
+ /* Check for already bound sockets */
|
|
|
+ if (sk->sk_state & PPPOX_CONNECTED) {
|
|
|
+ error = -EBUSY;
|
|
|
+ goto end;
|
|
|
+ }
|
|
|
+
|
|
|
+ /* Check for already disconnected sockets, on attempts to disconnect */
|
|
|
+ if (sk->sk_state & PPPOX_DEAD) {
|
|
|
+ error = -EALREADY;
|
|
|
+ goto end;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) {
|
|
|
+ error = -EINVAL;
|
|
|
+ goto end;
|
|
|
+ }
|
|
|
+
|
|
|
+ po->chan.private = sk;
|
|
|
+ po->chan.ops = &pptp_chan_ops;
|
|
|
+
|
|
|
+ {
|
|
|
+ struct flowi fl = {
|
|
|
+ .nl_u = {
|
|
|
+ .ip4_u = {
|
|
|
+ .daddr = opt->dst_addr.sin_addr.s_addr,
|
|
|
+ .saddr = opt->src_addr.sin_addr.s_addr,
|
|
|
+ .tos = RT_CONN_FLAGS(sk) } },
|
|
|
+ .proto = IPPROTO_GRE };
|
|
|
+ security_sk_classify_flow(sk, &fl);
|
|
|
+ if (ip_route_output_key(&init_net, &rt, &fl)) {
|
|
|
+ error = -EHOSTUNREACH;
|
|
|
+ goto end;
|
|
|
+ }
|
|
|
+ sk_setup_caps(sk, &rt->dst);
|
|
|
+ }
|
|
|
+ po->chan.mtu = dst_mtu(&rt->dst);
|
|
|
+ if (!po->chan.mtu)
|
|
|
+ po->chan.mtu = PPP_MTU;
|
|
|
+ ip_rt_put(rt);
|
|
|
+ po->chan.mtu -= PPTP_HEADER_OVERHEAD;
|
|
|
+
|
|
|
+ po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header);
|
|
|
+ error = ppp_register_channel(&po->chan);
|
|
|
+ if (error) {
|
|
|
+ pr_err("PPTP: failed to register PPP channel (%d)\n", error);
|
|
|
+ goto end;
|
|
|
+ }
|
|
|
+
|
|
|
+ opt->dst_addr = sp->sa_addr.pptp;
|
|
|
+ sk->sk_state = PPPOX_CONNECTED;
|
|
|
+
|
|
|
+ end:
|
|
|
+ release_sock(sk);
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_getname(struct socket *sock, struct sockaddr *uaddr,
|
|
|
+ int *usockaddr_len, int peer)
|
|
|
+{
|
|
|
+ int len = sizeof(struct sockaddr_pppox);
|
|
|
+ struct sockaddr_pppox sp;
|
|
|
+
|
|
|
+ sp.sa_family = AF_PPPOX;
|
|
|
+ sp.sa_protocol = PX_PROTO_PPTP;
|
|
|
+ sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr;
|
|
|
+
|
|
|
+ memcpy(uaddr, &sp, len);
|
|
|
+
|
|
|
+ *usockaddr_len = len;
|
|
|
+
|
|
|
+ return 0;
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_release(struct socket *sock)
|
|
|
+{
|
|
|
+ struct sock *sk = sock->sk;
|
|
|
+ struct pppox_sock *po;
|
|
|
+ struct pptp_opt *opt;
|
|
|
+ int error = 0;
|
|
|
+
|
|
|
+ if (!sk)
|
|
|
+ return 0;
|
|
|
+
|
|
|
+ lock_sock(sk);
|
|
|
+
|
|
|
+ if (sock_flag(sk, SOCK_DEAD)) {
|
|
|
+ release_sock(sk);
|
|
|
+ return -EBADF;
|
|
|
+ }
|
|
|
+
|
|
|
+ po = pppox_sk(sk);
|
|
|
+ opt = &po->proto.pptp;
|
|
|
+ del_chan(po);
|
|
|
+
|
|
|
+ pppox_unbind_sock(sk);
|
|
|
+ sk->sk_state = PPPOX_DEAD;
|
|
|
+
|
|
|
+ sock_orphan(sk);
|
|
|
+ sock->sk = NULL;
|
|
|
+
|
|
|
+ release_sock(sk);
|
|
|
+ sock_put(sk);
|
|
|
+
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+static void pptp_sock_destruct(struct sock *sk)
|
|
|
+{
|
|
|
+ if (!(sk->sk_state & PPPOX_DEAD)) {
|
|
|
+ del_chan(pppox_sk(sk));
|
|
|
+ pppox_unbind_sock(sk);
|
|
|
+ }
|
|
|
+ skb_queue_purge(&sk->sk_receive_queue);
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_create(struct net *net, struct socket *sock)
|
|
|
+{
|
|
|
+ int error = -ENOMEM;
|
|
|
+ struct sock *sk;
|
|
|
+ struct pppox_sock *po;
|
|
|
+ struct pptp_opt *opt;
|
|
|
+
|
|
|
+ sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pptp_sk_proto);
|
|
|
+ if (!sk)
|
|
|
+ goto out;
|
|
|
+
|
|
|
+ sock_init_data(sock, sk);
|
|
|
+
|
|
|
+ sock->state = SS_UNCONNECTED;
|
|
|
+ sock->ops = &pptp_ops;
|
|
|
+
|
|
|
+ sk->sk_backlog_rcv = pptp_rcv_core;
|
|
|
+ sk->sk_state = PPPOX_NONE;
|
|
|
+ sk->sk_type = SOCK_STREAM;
|
|
|
+ sk->sk_family = PF_PPPOX;
|
|
|
+ sk->sk_protocol = PX_PROTO_PPTP;
|
|
|
+ sk->sk_destruct = pptp_sock_destruct;
|
|
|
+
|
|
|
+ po = pppox_sk(sk);
|
|
|
+ opt = &po->proto.pptp;
|
|
|
+
|
|
|
+ opt->seq_sent = 0; opt->seq_recv = 0;
|
|
|
+ opt->ack_recv = 0; opt->ack_sent = 0;
|
|
|
+
|
|
|
+ error = 0;
|
|
|
+out:
|
|
|
+ return error;
|
|
|
+}
|
|
|
+
|
|
|
+static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd,
|
|
|
+ unsigned long arg)
|
|
|
+{
|
|
|
+ struct sock *sk = (struct sock *) chan->private;
|
|
|
+ struct pppox_sock *po = pppox_sk(sk);
|
|
|
+ struct pptp_opt *opt = &po->proto.pptp;
|
|
|
+ void __user *argp = (void __user *)arg;
|
|
|
+ int __user *p = argp;
|
|
|
+ int err, val;
|
|
|
+
|
|
|
+ err = -EFAULT;
|
|
|
+ switch (cmd) {
|
|
|
+ case PPPIOCGFLAGS:
|
|
|
+ val = opt->ppp_flags;
|
|
|
+ if (put_user(val, p))
|
|
|
+ break;
|
|
|
+ err = 0;
|
|
|
+ break;
|
|
|
+ case PPPIOCSFLAGS:
|
|
|
+ if (get_user(val, p))
|
|
|
+ break;
|
|
|
+ opt->ppp_flags = val & ~SC_RCV_BITS;
|
|
|
+ err = 0;
|
|
|
+ break;
|
|
|
+ default:
|
|
|
+ err = -ENOTTY;
|
|
|
+ }
|
|
|
+
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static struct ppp_channel_ops pptp_chan_ops = {
|
|
|
+ .start_xmit = pptp_xmit,
|
|
|
+ .ioctl = pptp_ppp_ioctl,
|
|
|
+};
|
|
|
+
|
|
|
+static struct proto pptp_sk_proto __read_mostly = {
|
|
|
+ .name = "PPTP",
|
|
|
+ .owner = THIS_MODULE,
|
|
|
+ .obj_size = sizeof(struct pppox_sock),
|
|
|
+};
|
|
|
+
|
|
|
+static const struct proto_ops pptp_ops = {
|
|
|
+ .family = AF_PPPOX,
|
|
|
+ .owner = THIS_MODULE,
|
|
|
+ .release = pptp_release,
|
|
|
+ .bind = pptp_bind,
|
|
|
+ .connect = pptp_connect,
|
|
|
+ .socketpair = sock_no_socketpair,
|
|
|
+ .accept = sock_no_accept,
|
|
|
+ .getname = pptp_getname,
|
|
|
+ .poll = sock_no_poll,
|
|
|
+ .listen = sock_no_listen,
|
|
|
+ .shutdown = sock_no_shutdown,
|
|
|
+ .setsockopt = sock_no_setsockopt,
|
|
|
+ .getsockopt = sock_no_getsockopt,
|
|
|
+ .sendmsg = sock_no_sendmsg,
|
|
|
+ .recvmsg = sock_no_recvmsg,
|
|
|
+ .mmap = sock_no_mmap,
|
|
|
+ .ioctl = pppox_ioctl,
|
|
|
+};
|
|
|
+
|
|
|
+static struct pppox_proto pppox_pptp_proto = {
|
|
|
+ .create = pptp_create,
|
|
|
+ .owner = THIS_MODULE,
|
|
|
+};
|
|
|
+
|
|
|
+static struct gre_protocol gre_pptp_protocol = {
|
|
|
+ .handler = pptp_rcv,
|
|
|
+};
|
|
|
+
|
|
|
+static int __init pptp_init_module(void)
|
|
|
+{
|
|
|
+ int err = 0;
|
|
|
+ pr_info("PPTP driver version " PPTP_DRIVER_VERSION "\n");
|
|
|
+
|
|
|
+ callid_sock = __vmalloc((MAX_CALLID + 1) * sizeof(void *),
|
|
|
+ GFP_KERNEL | __GFP_ZERO, PAGE_KERNEL);
|
|
|
+ if (!callid_sock) {
|
|
|
+ pr_err("PPTP: cann't allocate memory\n");
|
|
|
+ return -ENOMEM;
|
|
|
+ }
|
|
|
+
|
|
|
+ err = gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
|
|
|
+ if (err) {
|
|
|
+ pr_err("PPTP: can't add gre protocol\n");
|
|
|
+ goto out_mem_free;
|
|
|
+ }
|
|
|
+
|
|
|
+ err = proto_register(&pptp_sk_proto, 0);
|
|
|
+ if (err) {
|
|
|
+ pr_err("PPTP: can't register sk_proto\n");
|
|
|
+ goto out_gre_del_protocol;
|
|
|
+ }
|
|
|
+
|
|
|
+ err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto);
|
|
|
+ if (err) {
|
|
|
+ pr_err("PPTP: can't register pppox_proto\n");
|
|
|
+ goto out_unregister_sk_proto;
|
|
|
+ }
|
|
|
+
|
|
|
+ return 0;
|
|
|
+
|
|
|
+out_unregister_sk_proto:
|
|
|
+ proto_unregister(&pptp_sk_proto);
|
|
|
+out_gre_del_protocol:
|
|
|
+ gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
|
|
|
+out_mem_free:
|
|
|
+ vfree(callid_sock);
|
|
|
+
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static void __exit pptp_exit_module(void)
|
|
|
+{
|
|
|
+ unregister_pppox_proto(PX_PROTO_PPTP);
|
|
|
+ proto_unregister(&pptp_sk_proto);
|
|
|
+ gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP);
|
|
|
+ vfree(callid_sock);
|
|
|
+}
|
|
|
+
|
|
|
+module_init(pptp_init_module);
|
|
|
+module_exit(pptp_exit_module);
|
|
|
+
|
|
|
+MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol");
|
|
|
+MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)");
|
|
|
+MODULE_LICENSE("GPL");
|
Dmitry Kozlov